20101122121 has 4 divisors (see below), whose sum is σ = 20102241744. Its totient is φ = 20100002500.

The previous prime is 20101122059. The next prime is 20101122137. The reversal of 20101122121 is 12122110102.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20101122121 - 2¹¹ = 20101120073 is a prime.

It is a super-2 number, since 2×20101122121² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20101122191) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 532435 + ... + 568936.

It is an arithmetic number, because the mean of its divisors is an integer number (5025560436).

Almost surely, 2^20101122121 is an apocalyptic number.

It is an amenable number.

20101122121 is a deficient number, since it is larger than the sum of its proper divisors (1119623).

20101122121 is a wasteful number, since it uses less digits than its factorization.

20101122121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1119622.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 20101122121 its reverse (12122110102), we get a palindrome (32223232223).

The spelling of 20101122121 in words is "twenty billion, one hundred one million, one hundred twenty-two thousand, one hundred twenty-one".